Apparatus for automatically controlling the paper feed speed in large paper bag machiones



Apnl 15, 1958 w. PAUL 2,830,811

APPARATUS FOR AUTOMATICALLY CONTROLLING THE PAPER FEED SPEED IN LARGE PAPER BAG MACHINES Filed July 27, 1953 V 2 Sheets-Sheet 1 Inventor: Z762 Pa a Z/ W. PAUL 2,830,811 TOMATICALLY CONTROLLING THE PAPER IN LARGE PAPER B AG MACHINES April 15, .1958

APPARATUS FOR AU FEED SPEED 2 Sheets-Sheet 2 Filed July 27, 1953 FIG.3

INVENTOR WALTER PAUL ATTORNEYS United States Patent APPARATUS FOR AUTOMATICALLY CONTRQL- LING THE PAPER FEED SPEED IN LARGE PAPER BAG MACHINES Walter Paul, Lengerich, Westphalia, Germany, assignor to lFritz Htilscher and Alfred Windrniiller, trading as Windmiiller and Htilscher, Lengerich, Westphalia, Germany Application .luly27, 1953, Serial No. 370,515

Claims priority, application Germany August 4, 1952 2 Claims. (Cl. 2712.6)

This invention relates to apparatus for automatically controlling the paper feed speed in large paper bag machines, the mechanical control elements employed in the said apparatus consisting essentially of a continuously regulable transmission and a differential gear, and regulation of the paper feed speed being eifected through the intermediary of a further differential gear inteiposed in the main drive of the feed mechanism. The mechanical control elements are brought into operation and/or driven by means of a reversible electric motor which is itself controlled by means of a photoelectric directing device.

When an electric motor is used for bringing the mechanical control elements into operation and/or driving them, disadvantages arise. More particularly, the fact that the loading of the electric motor dififers depending on whether the rotation is counterclockwise or clockwise has the disadvantageous effect that the motor lags longer in one direction than in the other. As a result, there are different regulation paths for the two cases, which has a disadvantageous effect on the regulation, which would be uniform in both directions.

The object of the invention is to remove these disadvantages. According to the invention, the bringing into operation and/ or the driving of the mechanical control elements is or are effected from the drive of the paper bag machine. Preferably, electrically actuated couplings known per se, for instance magnetic couplings, are interposed in the drive for bringing into operation and/or driving the mechanical control elements, one of these couplings being used for increasing the paper feed speed and another for decreasing said speed.

One embodiment of the control apparatus according to the invention is illustrated in the accompanying drawing in which:

Fig. 1 is a diagrammatic representation of the control device according to the invention in plan,

Fig. 2 is a diagrammatic illustration of the photoelectric part of the control device according to Fig. l in side elevation, and

Fig. 3 shows a plan view of electro-magnetic couplings of a type which may be used, viewed in the direction of arrow A in Fig. 2 in order to more distinctly illustrate the symbolic representation in Fig. 1.

In Fig. 1 the electrical conductors are shown in dasl1 lines; in Fig. 2 in full lines. A detailed description of the control installation is given as follows:

In Figs. 1 and 2 the material web to be processed is denoted by 1. It carries in uniformly spaced relation beam prints 2 on the several workpiece lengths to be detached at a predetermined spot. The material web 1 is pulled by the advancing roller 3 and moves in the direction of an indicated arrow to a cutting device 4 which detaches the single workpieces 1' from the web. The cutting device 4 is driven from the electromotor 5 through gears 6 and 7. From the same motor 5 also the advancing rollers 3, 3' are driven. For this purpose there is,

e. g., at the end of knife shaft 8 a bevel wheel 9 which meshes with an additional bevel wheel 10. The same is connected with an interchangeable gear 11 which is so selected that its circumference corresponds to the length of theworkpiece to be detached. The distance of the beam prints 2 on Web 1 also equals the workpiece length. The drive for the advancing roller is transmitted by the gear 11 to a gear 13 through an intermediate gear 12 journaled on a lever 12'. Gear 13 is secured on a shaft 14, at the other end of which an input sunwheel 15a of a diiferential mechanism 15 is fastened. The differential mechanism 15 may be of any known construction. In the illustrated example it concerns a bevel gear differential mechanism with the two sun wheels 15a and 15b and two planet wheels 15:: and 15d. The planet gears 15c and 15d are journaled in the spider element 19 which itself is provided on its outer side with spur gear teeth. The output sun gear 15b is fastened to a shaft 14' which at its other end carries a bevel gear 16 which in turn meshes with a bevel gear 17. Bevel gear 17 is secured to shaft 18 which also carries the advancing roller 3 and drives the same.

By the appropriate gear 11 between two cuts of the cutting device 4 the web is advanced by advancing roller 3 by an amount which corresponds to the distance of the beam prints on the web. Owing to unavoidable small irregularities as to the spacing of the beamprints or owing to slippage in the advancing means and climatic influences, the detached section length will not always agree with the distance between prints whereby the prints on the detached workpieces will be improperly shifted. In order to be able to compensate for such errors in the print position, a fine adjustment of the advancing roller speed and of the length of the detached section is provided. For this purpose with gear 13 an additional gear 2% meshes which in turn drives a shaft 21. The shaft 21 constitutes the input side of a steplessly controllable drive 22, the output side of which is constituted by shaft 23. The steplessly controllable drive can be of any known construction and, e. g., can be constructed as a positively infinitely variable drive. In the illustrated example two conical pulleys 22a and 22b are selected which provide by a belt 22d shiftable by belt fork 22c, a gradually controllable transmission ratio between the shafts 21 and 23. At the end of shaft 23 is the input sunwheel of a second differential mechanism 24 represented as bevel gear differential mechanism, a shaft attached to the output sun gear of which drives a bevel gear 25. This in turn meshes with bevel gear 26, a shaft attached to which in turn drives a worm 27. The worm 27 meshes with worm gear 28 mounted on a shaft which transmits the drive to gear 29 which in turn meshes with the spur gear teeth of element 19 of the differential mechanism 15. Thereby the element 19 can be turned together with the planet gears 15c and 15d whereby in a known manner an altered speed is imparted to output sun gear 15b.

By changing the position of belt 22d on the cones 22a and 22b the drive of element 19 is changed. By rotation of element 35 of differential mechanism 24 the drive of element 19 is changed for the duration of this rotation and thus is altered in a transitory manner.

The drive for rotation of spider element 30 carrying the planet gears of differential 24 and for changing the position of belt 22d by means of belt fork 220 is also derived from the driving motor 5. For this reason the shaft 21 carries a bevel gear 40a which drives through bevel gear 40b shaft 41 and through additional bevel gears 42 the shaft 43 and throughadditional bevel gears 44 the gear 45. The gear 45 (see also Fig. 3) is located on the input side of an electromagnetic coupling 50 and simultaneously meshes with gear 46 which is located on the input side of a second electromagnetic coupling 49. Located on the output side of the electromagnetic couplings 49 and 50 are gears 47 and 48, respectively, which are in driving relation to one another by an intermediate gear 51. The operation of the above described arrangement is as follows:

If, for example, the magnetic coupling 50 is energized, power is transmitted from gear 45 to gear 46, thence through the electromagnetic coupling 50 to gear 48 which turns in a direction opposite to that of gear 45. If, then, instead of coupling 50 the electromagnetic coupling 49 is energized, the drive from gear 45 goes through coupling 49 to gear 47 and thence through gear 51 to gear 48 which now, owing to the intermediate gear 51, turns in the direction of gear 45. By selective energization of one or the other electromagnetic couplings a drive in one or the other direction may be had.

With the delivery gear 48 of the electromagnetic coupling the gear 52 is rigidly connected which drives through an intermediate gear 53 the gear 54. The same is connected to worm 55a which in turn meshes with a worm gear 55b. Worm gear 55b drives shaft 56 which carries a gear 57 and worm 58a. Gear 57 meshes with the exterior teeth of element 30 of the ditierential mechanism 24. Worm 58a meshes with worm gear 5812 which causes an adjustment of belt 22d on the cones 22a and 2217 by means of belt fork 220. The energization of the electromagnetic coupling is effected by a photoelectric control installation.

Since such photoelectric control installations in this field are well known and do not constitute a part of the claimed invention, it is deemed suflicient to furnish a short description of the essential parts diagrammatically represented in the drawing and of their function.

A light source 31. and photoelectric cell 33 are arranged in such relation to the paper web that the photocell receives the light reflected by the web adjacent the beam prints 2 which varies at the passage of each beam print and thereby generates in the photocell a current impulse. These impulses by the use of an electrical device 34 and the selector switches 35 and 36 rotating in the ratio 1:1 to the knife shaft, are used in a known manner to excite the magnet clutch 50 or 49 according to requirement. An example of such an electrical device and selector switches is shown in the patent to Gulliksen No. 2,249,820, especially Fig. 2.

The mode of operation of the control device is as follows:

If, for example, the beam print on the cut-01f workpieces lies too far in front, the reflection of the light is changed too soon, which causes-owing to selector switch 35, 36the electromagnetic clutch 49, for instance, to be energized which causes a transitory decrease of the advancing speed through the differential mechanism 24 and a small constant diminution of the advancing speed on the steplessly controllable drive 22 which acts through element 19 of the differential mechanism 15 disposed in the main drive of the advacing roller on the same.

If the beam print is in the right position on the cut-off workpieces, the electric impulse generated by the changing reflection is interrupted at the selector switch 35, 36 so that none of the electromagnetic clutches is energized.

If the pressure on the cut-off workpieces lies too far in the rear, the light reflection is changed too late which, owing to selector switch 35, 36, causes clutch 50, for instance, to be energized which efiects a variation of the advancing speed in the opposite direction.

It must still be stated that even if the electromagnetic couplings 49 and 50 are not energized and thus element 4 30 of the diiferential mechanism 24 and the belt fork 220 are stationary, yet the steplessly controllable drive 22, shaft 23, the sun gears of the ditferential mechanism 24, and thus finally also element 19 of the differential mechanism are always in motion. As a result, the output sun gear 15b of differential mechanism 15 rotates at a speed changed with respect to the input sun gear 15a which initial rotary speed at a transmission ratio of 1:1 of the steplessly controllable drive (positively, infinitely variable) 22 results in the advancing speed required for attaining t1 2e desired section length. For this purpose the transmission ratio of the drive from interchangeable gear 11 through gears 12, 13, 15a, 15b, 16, 1.7 to the advancing roller 3 is expediently so selected that with element 19 stationary a little more than the desired section length between two cuts is advanced. The rotation of element 19, therefore, causes a decrease of the starting speed of the differential mechanism 15 whereby the power expenditure for rotating element 19 equals almost zero, since in this case it is driven, as is well known, from gear 15a through the planet gears and braking from outside is necessary to control its motion. This braking is brought about in an ingenious manner by the worm drive 27, 28 which is self-braking. The forces to be transmitted by the mechanical control elements, thus, are merely large enough that they release the worm and overcome the remaining friction. The mechanical control elements are therefore kept small in spite of high advancing forces.

ential drive including a driving, a driven and a control member which is placed in the main drive of the advancing mechanism, and a positive infinitely variable drive, and a second differential drive, which are arranged in series in a branch drive geared to the driving source as the main drive for the advancing mechanism, said branch drive controlling the main drive by driving the control member of the first difierential drive.

2. A control apparatus according to claim 1, including electromagnetic elements consisting of two electrically actuated clutches arranged in an additional drive geared to said main drive of the advancing mechanism for varying the transmission ratio of said positive infinitely variable drive and for simultaneously driving the control member of said second differential drive, one clutch rotating to the right and the other clutch rotating to the left, whereby upon connecting one or the other clutch the speed of the branch drive to the control member of said first differential drive and accordingly also of the main drive and of the advancing mechanism is either increased or decreased.

References Cited in the file of this patent UNITED STATES PATENTS 1,999,164 Avery Apr. 23, 1935 2,052,256 Shoults Aug. 25, 1936 2,180,202 Hallden Nov. 14, 1939 2,180,203 Hallden Nov. 14, 1939 2,201,581 Hallden May 21, 1940 2,205,333 Redd June 25, 1940 2,228,300 Cohen Jan. 14, 1941 2,249,820 Gulliksen July 22, 1941 2,321,647 Brougham et a1. June 15, 1943 2,548,136 Auer Apr. 10, 1951 

